1. Field of the Invention
The invention relates to providing facsimile (fax) services over the telephone network via application software for such services and involves a telephone network digital computer platform for supporting such application software.
2. Description of the Prior Art
The facsimile machine has become ubiquitous in present day communication for transmission of documents. Facsimile transmission over the Public Switched Telecommunications Network (PSTN) annually generates billions of dollars in toll revenues. A variety of facsimile related services and enhanced services are currently available, such as Call Answer, Fax Store and Forward, Fax Mailbox, and the like. Generally, such services are provided by dedicated systems specifically designed for the service and for the hardware environment in which the system will be deployed. Such systems tend to lack flexibility, in that desired changes in functionality often require extensive, and hence expensive, modifications to the application software. Additionally, application software for providing such services are not portable in that a change in hardware environment usually requires substantial application software re-writing. Although such systems are usually computer based, such systems can only perform the functions for which they were designed and, thus, cannot also be utilized to perform general purpose data processing. Also, such systems generally do not have access to data bases stored on general purpose computers. Additionally, if it is desired to provide a wide variety of services, utilization of a large number of dedicated systems tends to be prohibitively expensive.
Since the divestiture, the Bell Operating Companies (BOCs) and Independent Telephone Companies (Telcos) have been seeking ways to increase the return on their primary asset; viz, the installed network. One source of increased revenue would be to offer new facsimile related services that integrate into, or interface with the existing network, resulting in greater utilization thereof. It is generally difficult for BOCs and Telcos to provide new services because network switches are designed to switch calls, not support data base or special service related functionality. Each Central Office (CO) utilizes a predetermined set of functions provided by the switch manufacturer. Only the manufacturer could add new services to the switching system which usually involves substantial lead times, such as two years or more. Additionally, the switch manufacturers have been particularly slow in responding to the needs of the BOCs and Telcos for enhanced service provisioning. A major limiting factor to providing new facsimile related services is a dependence on the telephone switch provider for implementing the capabilities required by these new services.
In addition to the above disadvantages, it is believed that currently available facsimile service systems do not have the capability of sending and receiving facsimile transmissions over a currently established voice connection. Present day systems are believed to terminate a voice connection and then re-dial a fax machine for the facsimile transmission. It is furthermore believed that present day systems do not have the capability of common storage of voice and fax images in the same data base. Separate facilities are believed to be required. It is furthermore believed that present day facsimile systems effect fax transmissions in an inefficient interactive mode utilizing flow control such as transmitting one Rage at a time.
Although the system of said U.S. Pat. No. 5,138,004 overcomes the disadvantages described above with respect to voice communication, the advantages realized by the platform of said U.S. Pat. No. 5,133,004 for voice has not, prior to the present invention, been achieved for fax.